Need an engine rebuild? Or vane pump drive gear? (UPDATE:video)

[Stevesnj]

I have had, what seems like a valve train knock, after my head gasket replacement 4 years ago. I thought it was the vane pump gear knock (could be the drive gear). I diagnosed the vane pump knock by when I turned the steering wheel to lock the knock would go away so I just replaced the vane gear (OEM) and a rebuilt pump(NAPA) but the knock continues and goes away after wheel lock still. Opinions or suggestions before I rebuild the engine.

 

[brian]

sounds like you just want to rebuild the engine.

 

[Stevesnj]

sounds like you just want to rebuild the engine.

If I can avoid it I will.

 

[Stevesnj]

Anyone know if the vane pump drive gear is replaceable on it's own or do I have to remove the crankshaft and oil pump gear to replace it?

 

[jonheld]

Anyone know if the vane pump drive gear is replaceable on it's own or do I have to remove the crankshaft and oil pump gear to replace it?

Are you referring to the power steering pump in a 1FZ-FE engine?
I ask because there are several threads relating to pump drive gear noise that seem to be resolved by proper installation of the pump drive gear. Wits End makes a tool to hold the drive gear without damage so the gear can be properly seated while tightening the nut to torque spec.

 

[Stevesnj]

Are you referring to the power steering pump in a 1FZ-FE engine?
I ask because there are several threads relating to pump drive gear noise that seem to be resolved by proper installation of the pump drive gear. Wits End makes a tool to hold the drive gear without damage so the gear can be properly seated while tightening the nut to torque spec.

I replaced the gear with new OEM and a rebuilt pump. I don't need to change that. But the knock continues and disappears after I turn the wheel to hard lock to the left or right. I read those threads and just wondering if the drive gear (on the engine) is bad.

 

[jamarquardt22]

I fail to see how this sounds like a engine rebuild. All signs point to somthing steering related.

 

[brian]

I fail to see how this sounds like a engine rebuild. All signs point to somthing steering related.

that was my point as well, just not a clearly put.

 

[jamarquardt22]

sounds like you just want to rebuild the engine.

Sounds clear to me.

 

[Stevesnj]

Sounds clear to me.

Well If it's cheaper to replace just the drive gear I'd just do that. Just seems odd this noise goes away when I turn the steering to lock. Without someone else hearing it I guess it's difficult to tell. I don't have the funds for a rebuild but if it's just the gear and I can replace it myself I'd rather do that which should be much less expensive.

 

[jonheld]

The PS pump gear is driven by an intermediate gear off of the crank, so you're looking at pulling apart the front of the motor.
The FSM is available for download in the resources section.

 

[Stevesnj]

The PS pump gear is driven by an intermediate gear off of the crank, so you're looking at pulling apart the front of the motor.
The FSM is available for download in the resources section.

Thanks Jon

I'm assuming it's this gear behind the crank rotor gear? Looks like oil pan, head, timing gear, has to come off just to replace that gear.

 

[Crusha]

Before you start tearing things apart, make sure you pinpoint the noise.

It could be something completely unrelated to your P/S.

Especially if it appeared after you did a head gasket.

 

[Stevesnj]

Before you start tearing things apart, make sure you pinpoint the noise.

It could be something completely unrelated to your P/S.

Especially if it appeared after you did a head gasket.

Thanks. Yeh thats why i wanted to get an opinion on here from my description. It's just odd that it goes away on steering lock. Some have mentioned a mechanic near Philly that works on LC's. Whats his name or shop name? Maybe he can diagnose it. Also does he do engine rebuilds? Thanks for any help! I need to get back on the trails! Been a few years too long!!!!

 

[Crusha]

Get a cheap stethoscope, and have someone hold the wheel at full lock while you try to pinpoint the noise.

If you can't get someone to help, use a tie down strap, or piece of rope, to secure the steering wheel at full lock.

Amazon product ASIN B01BUJZBOO

 

[jonheld]

Thanks Jon
I'm assuming it's this gear behind the crank rotor gear? Looks like oil pan, head, timing gear, has to come off just to replace that gear.

I think you're 1 gear off. I believe the PS pump gear is run by the oil pump gear. However, there are guys on the 80s forum that know this stuff cold. I would ask there before trusting anything I say...at least on this topic

 

[JeepinPete]

I can tell you from experience that noises travel in these trucks. Start with the easy things first. Pull the belts, noise still there? Pull the PS pump out of the engine and start it up, noise still there? I had a idler bearing sound like a transmission oil pump, and a loose fan nut sound like a rod knock. I generally know my sounds, but my damn truck has humbled me

 

[RWBeringer4x4]

Get a cheap stethoscope, and have someone hold the wheel at full lock while you try to pinpoint the noise.

If you can't get someone to help, use a tie down strap, or piece of rope, to secure the steering wheel at full lock.

Amazon product ASIN B01BUJZBOO

Stethescope is seriously one of the best $10 I've ever spent and is super useful for diagnosing random noises. I can literally hear coolant/oil flowing through the galleys with one of these.

 

[Stevesnj]

Stethescope is seriously one of the best $10 I've ever spent and is super useful for diagnosing random noises. I can literally hear coolant/oil flowing through the galleys with one of these.

So I got a stethoscope and it sounds like its coming from above the timing chain tensioner which I replaced with OEM when I did the head gasket. I took a short video. The sound is the lower pitch sound like a rod knock but it isn't a rod knock I scoped all under the oil pan area. Could a bad chain slipper cause a rod knock sound? Thanks for any help...again.

 

[RWBeringer4x4]

Does the knocking change with RPM if you rev the engine or is it consistent? Any chance you have a rocker hitting the underside of the valve cover?